Structural and chemical analysis of hydroxyapatite (HA)-Boron nitride (BN) nanocomposites sintered under different atmospheric conditions

Calcium phosphate derivatives have been widely employed in medical and dental applications for hard tissue repair, since they are the main inorganic constitution of hard tissue; such as bones and teeth. Owing to their excellent osteoconductive and bioactive properties, Hydroxyapatite (HA) based ceramics are the best candidates of this group for medical, bioscience and dental applications. However, when replacing a bone or tooth, HA is not able to sustain similar mechanical properties. In this study, to improve the mechanical properties, nanoscale hexagonal boron nitride (nhBN) with different compositional percentages was added to the nano HA (nHA) to form composites. The effect of compositional changes and sintering parameters on microstructural and morphological properties of the ceramic composites was comparatively investigated. Detailed chemical characterization of the composite materials was carried out using X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Raman Spectroscopy and Energy Dispersive X-ray Spectroscopy (EDS), while Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) investigations were employed to monitor morphological and surface features. Additional Transmission Electron Microscopy (TEM) investigations were carried out to reveal the nanostructure and crystal structure of the composites.